I want to obfuscate a single .dll file (to hide constants). When I confuse .dll compiled as release for any processor AND application is started from .exe - everything works fine.
Unfortunately this .dll is meant to be a "key" for some things in our database that we want to give to someone else to use. But I don't want them to be able to recover this source code in like 2-3 clicks by DotPeek or any other reverse engineering tool for C#. They are still testing their things, so they start their app from Visual Studio.
When I add non-obfuscated .dll to my test project as reference - everything is fine. But when I add already obfuscated .dll as reference I get 'FatalExecutionEngineError'. And that's unfortunately the whole point - I want them to have this .dll for usage and testing purposes, but after obfuscation it may not be possible for them to use it from Visual Studio.
Am I doing something wrong or should I just use a different obfuscation tool?
Related
For example, I have two projects let's say project A and project B. I have the source code of project A and project B.
Then in my project A, there are some .a files made by project B. Project A use those .a files to compile and run.
The question is, when I run project A, I want to debug the codes in those .a file. Is it possible? If possible, how can I do it?
I'm using Visual Studio for Mac.
Note: Project A is written in C# and Project B is written in C++.
It‘s a Xamarin project.
If you have no source code of project B, then you can only debug in assembly mode.
If you do have source code of project B, make sure .a files reserving debug info(like dwarf) and use lldb source-map technique to perform mapping.
But, if you have .a file's source, why not just build with project B source.
You need to attach with Visual studio to the running process. Attaching to process with Visual Studio is done with Alt + Ctrl + P on windows.
In case the code you wish to debug is run at startup of your app, place your breakpoints and add a 30 seconds sleep (before any of your breakpoints) so you have time to attach.
When picking the process, make sure to tick the right code types to debug by clicking Select...
If you have access to source code for both projects, I would recommend to create a solution with both projects, as you may be able to use different language projects on same solution (please check this, as an example: https://social.msdn.microsoft.com/Forums/en-US/737e2bf3-86ab-49aa-bafa-b3a3d05ce826/mixed-languages-in-visual-studio?forum=csharpgeneral).
To debug C++ code inside the C# project, check options for your current Visual Studio version, as suggested in this post:
Debug c++ dll in C#
Set project A (C#) as start project, and, if references are correct, you should be able to debug .a files referenced from project B.
You can build both Debug and Release into separate preset directories in any IDE. This is a good practice for all builds - using Configuration -> Release and Debug. You may name the libraries as libname_d.lib and libname.a so they do not get mixed up.
Then you can link to the appropriate library (libname_d.a) while debugging. Its a matter of choice - some may not recommend linking multiple projects into the same Solution (or Workspace), since each separate library will have a separate set of tests. These are difficult to manage in a single project.
Ideally, each library can be coded and tested separately and built into Release and Debug. This way functionality can be isolated and object-based design can be followed.
Its also important to understand the difference between .a (Linux, Mac) and .lib (Windows) - see here - What's the difference between .lib and .a files?
I'm about to start developing a desktop application (WPF) based on a "plugin" architecture, and was going to use MEF (and its DirectoryCatalog) to discover and load plugin assemblies. We're going to be developing many plugins, so it seems sensible to keep them in separate VS solutions rather than bloat the "core" application solution, but having only ever worked on single, standalone solutions, I suspect this is going to make debugging a bit tricky. I'm using VS2013 if that makes a difference.
I'm assuming that I'll still be able to step into a plugin in scenarios where the "core" application calls a method in that plugin? And I'm guessing that once in there, I'll be able to set breakpoints in those source code files that have been "visited"? But what if I want to add a breakpoint to a different source code file - one that hasn't been visited while stepping-through? How can I open that file? In a single solution I could just open it via Solution Explorer, but not (I'm guessing) when it's in a separate assembly.
I'm trying to pre-empt any problems I might have with this multi-solution approach, and wondered if VS had any clever features to simplify some of this stuff. Having separate solutions also means first compiling the plugin solution(s) that I want to test, then compiling and running the "core" application solution. While it's only a couple of extra mouse clicks, are there (again) any VS features that could help here?
This is a common scenario and not tricky at all.
In the project properties of your plug-ins, go to Debug -> Start Action and set Start external program to the executable of your core application.
This way, you only have to compile your core application once (probably using a build script that just builds everything), and debugging a plug-in will start the core application with the debugger attached and you can debug the plug-in (as soon as your core apllication loads the plug-in assembly).
Also keep in mind that you can dettach the debugger from the running application, switch to another instance of Visual Studio with another solution opened, and again attach to your running application. This comes in handy if you e.g. debug your plug-in and want to set or use existing break points in your core application.
As long as Visual Studio is able to find the debugging symbols (the *.pdb files), stepping through the code of e.g. your core application while debugging your plug-in is also no problem.
I see two ways to do this.
The more comfortable option:
1. You can add the external solution to the core solution.
Walkthrough: Adding an existing Visual Studio solution to another solution
By doing this you can organize your solution to reference the code and still keep each plugin solution separate at the same time.
You just reference those plugin solutions from your core solution that you currently want to work on. Also, using this approach you can organize the other solutions just like you would with normal projects and move thembetween virtual solutios folders to your liking until you have the most adequate folder structure.
Quote from the article:
The nice thing about this approach is that not only are all the
projects now in one solution but at any time, you can open the
separate solutions without impacting the "master" solution and vice
versa.
The files in the references solution can be opened and edited just like any other file from your "normal" projects, and of course, you can set breakpoint like in any other code file, too.
This way you can both edityour code and step through it, which I personally find much more convenient than switching and attaching to multiple processes.
2. Add the PDB files.
Put the DLLs with their corresponding PDBs of those plugins you want to debug into a folder and configure your core application to use that folder for the DirectoryCatalog. This enables you to step into the plugin code, but you will not be able to edit them.
#Andrew
Regarding debugging, it shouldn't be an issue as long as you drop the .pdb files with assembly in directory which you are using as DirectoryCatalog.
Regarding building plugin solution before Core- as you have 1 build file for each solution, you should check if you can write msbuild commands in a .bat file to get it executed one after other.
Besides all the above suggestions, another way to debug is to attach your addin solution to the running core process. Attach to Running Processes with the Visual Studio Debugger
I am working on an assembly that handles various color transformations. When I load the assembly into a new project to test, if there happens to be an bug in the assembly, Visual Studio opens the offending code from the DLL. I can step through all of the code in the assembly.
I definitely don't want the code to be so easily visible/available. I would like the code to be somewhat "locked" in the assembly.
How can I set the DLL to simply throw some sort of error instead of opening?
Edit
I'm not interested in the code being "safe" and I have no need to obfuscate. This library is being used internally and the code itself is perfectly accessible to tohers. What I don't want is for someone using the library to find themselves suddenly debugging the assembly. If there is a problem, I prefer to have an error thrown instead of the assembly code opening in Visual Studio.
This is happening because you have VS installed on the machine, and because you are deploying the PDB files - you will not get this dialogue box if VS is not installed.
Additionally:
Do not deploy code that has been built in the Debug configuration. These contain additional information that helps with debugging.
Make sure you do not deploy the PDB files with the executables. Same as above, and they are not needed for running the code.
Both these will help, but any assembly would be easily decompiled with reflector, so you may also want to investigate obfuscators to stop other programmers from easily seeing your code.
There is a list of C# obfuscators here : http://www.csharp411.com/net-obfuscators/
What you need is to obfuscate your binaries.
Basically if you want your code to be safe and you dont want your classes are exposed to others, you should definitely need to Obfuscate your code.
To obfuscate your code you can use DotFuscator, it is included with Visual Studio installation.
check my article on it.
http://www.codeproject.com/KB/dotnet/code_security.aspx
I'm getting System.IO.FileNotFoundException: The specified module could not be found when running C# code that calls a C++/CLI assembly which in turn calls a pure C DLL. It happens as soon as an object is instantiated that calls the pure C DLL functions.
BackingStore is pure C.
CPPDemoViewModel is C++/CLI calling BackingStore it has a reference to BackingStore.
I tried the simplest possible case - add a new C# unit test project that just tries to create an object defined in CPPDemoViewModel . I added a reference from the C# project to CPPDemoViewModel .
A C++/CLI test project works fine with just the added ref to CPPDemoViewModel so it's something about going between the languages.
I'm using Visual Studio 2008 SP1 with .Net 3.5 SP1. I'm building on Vista x64 but have been careful to make sure my Platform target is set to x86.
This feels like something stupid and obvious I'm missing but it would be even more stupid of me to waste time trying to solve it in private so I'm out here embarrassing myself!
This is a test for a project porting a huge amount of legacy C code which I'm keeping in a DLL with a ViewModel implemented in C++/CLI.
edit
After checking directories, I can confirm that the BackingStore.dll has not been copied.
I have the standard unique project folders created with a typical multi-project solution.
WPFViewModelInCPP
BackingStore
CPPViewModel
CPPViewModelTestInCS
bin
Debug
Debug
The higher-level Debug appears to be a common folder used by the C and C++/CLI projects, to my surprise.
WPFViewModelInCPP\Debug contains BackingStore.dll, CPPDemoViewModel.dll, CPPViewModelTest.dll and their associated .ilk and .pdb files
WPFViewModelInCPP\CPPViewModelTestInCS\bin\Debug contains CPPDemoViewModel and CPPViewModelTestInCS .dll and .pdb files but not BackingStore. However, manually copying BackingStore into that directory did not fix the error.
CPPDemoViewModel has the property Copy Local set which I assume is responsible for copying its DLL when if is referenced. I can't add a reference from a C# project to a pure C DLL - it just says A Reference to Backing Store could not be added.
I'm not sure if I have just one problem or two.
I can use an old-fashioned copying build step to copy the BackingStore.dll into any given C# project's directories, although I'd hoped the new .net model didn't require that.
DependencyWalker is telling me that the missing file is GPSVC.dll which has been suggested indicates security setting issues. I suspect this is a red herring.
edit2
With a manual copy of BackingStore.dll to be adjacent to the executable, the GUI now works fine. The C# Test Project still has problems which I suspect is due to the runtime environment of a test project but I can live without that for now.
Are the C and C++ DLLs in the same directory as the C# assembly that's executing?
You may have to change your project output settings so that the C# assembly and the other DLLs all end up in the same folder.
I've often used the Dependency Walker in cases like this; it's a sanity check that shows that all the dependencies can actually be found.
Once your app is running, you may also want to try out Process Monitor on the code you are running, to see which DLLs are being referenced, and where they are located.
The answer for the GUI, other than changing output settings, was the addition of a Pre-Build Step
copy $(ProjectDir)..\Debug\BackingStore.* $(TargetDir)
The answer for the Test projects was to add the missing DLL to the Deployment tab of the testrunconfig. You can either do so by directly editing the default LocalTestRun.testrunconfig (appears in Solution under Solution Items) or right-click the Solution and Add a new test run config, which will then appear under the main Test menu.
Thanks for the answers on this SO question on test configurations for leading me to the answer.
The reason why this happens is because you either are loading DLLMAIN from managed code, before the CRT has an opportunity to be initialized. You may not have any managed code, be executed DIRECTLY or INDERECTLY from an effect of DllMain notifications. (See: Expert C++/CLI: .Net for Visual C++ Programmers, chapter 11++).
Or you have no native entrypoint defined wahtsoever, yet you have linked to MSVCRT. The CLR is automatically initialized for you with /clr, this detail causes a lot of confusion and must be taken into account. A mixed mode DLL actually delay loads the CLR through the use of hot-patching all of the managed entry point vtables in your classes.
A number of class initialization issues surround this topic, loader lock and delay loading CLR are a bit trickey sometimes. Try to declare global's static and do not use #pragma managed/unmanaged, isolate your code with /clr per-file.
If you can not isolate your code from the managed code, and are having trouble, (after taking some of these steps), you can also look towards hosting the CLR yourself and perhaps going through the effort of creating a domain manager, that would ensure your fully "in-the-loop" of runtime events and bootstrapping.
This is exactally why, it has nothting todo with your search path, or initialization. Unfortunately the Fusion log viewer does not help that much (which is the usual place to look for .NET CLR assembly binding issues not dependency walker).
Linking statically has nothing todo with this either. You can NOT statically link a C++/CLI application which is mixed mode.
Place your DLLMAIN function into a file by itself.
Ensure that this file does NOT have /CLR set in the build options (file build options)
Make sure your linking with /MD or /MDd, and all your dependencies which you LINK use the exact same CRT.
Evaluate your linker's settings for /DEFAULTLIB and /INCLUDE to identify any possiable reference issues, you can declare a prototype in your code and use /INCLUDE to override default library link resolution.
Good luck, also check that book it's very good.
Make sure the target system has the correct MS Visual C runtime, and that you are not accidentally building the C dll with a debug runtime.
This is an interesting dilemma. I've never heard of a problem loading native .DLLs from C++/CLI after a call into it from C# before. I can only assume the problem is as #Daniel L suggested, and that your .DLL simply isn't in a path the assembly loader can find.
If Daniel's suggestion doesn't work out, I suggest you try statically linking the native C code to the C++/CLI program, if you can. That would certainly solve the problem, as the .DLL would then be entirely absorbed into the C++/CLI .DLL.
Had the same problem switching to 64-bit Vista. Our application was calling Win32 DLLs which was confusing the target build for the application. To resolve it we did the following:
Go to project properties;
Select Build tab;
Change 'Platform target:' option to x86;
Rebuild the application.
When I re-ran the application it worked.
I have a project which has a calling structure similar to this:
main project/application
my library code
someone else's library code
my library code
Everything's written in C#, and I have access to 'someone else's library code'. Their code is not included in my project, because it's open source and not my code. I can make debug versions of all the libraries, and I've done so.
That 'someone else's library code (SELC, I guess?) is throwing an exception in a heisen-bug kind of way, and I'm trying to track it down and maybe submit a bugfix to the project maintainer. Problem is, my debugging stack is stopping at my library code, and lists the SELC as 'external' and I can't debug into it. I've copied the pdb files as well as the debug version of the library into the debug directory of my application, and still no luck; I can't seem to debug into their code, and I can't step into it at all.
Once upon a time, back in vs6 days, I could do this-- have two different projects open at the same time in two different environments, and have the debugger trace across dll boundaries from one project into another. I'd assume that functionality remains, because it's just so dang useful.
Any suggestions?
I've looked for this answer but not found it, so if this is a dupe, just let me know where to look.
Do you have "Just My Code" turned on in Visual Studio's debugging options?
If you have the sources (as i read from you), you can make an project with their source code, and then add the project to your solution.
In visual studio the project in .csproj file , and solutions in .sln file.